#include "node_stat_watcher.h"
#include "async-wrap.h"
#include "async-wrap-inl.h"
#include "env.h"
#include "env-inl.h"
#include "util.h"
#include "util-inl.h"

#include <string.h>
#include <stdlib.h>

namespace node {

using v8::Context;
using v8::FunctionCallbackInfo;
using v8::FunctionTemplate;
using v8::HandleScope;
using v8::Integer;
using v8::Local;
using v8::Object;
using v8::Value;

void StatWatcher::Initialize(Environment* env, Local<Object> target)
{
    HandleScope scope(env->isolate());

    Local<FunctionTemplate> t = env->NewFunctionTemplate(StatWatcher::New);
    t->InstanceTemplate()->SetInternalFieldCount(1);
    t->SetClassName(FIXED_ONE_BYTE_STRING(env->isolate(), "StatWatcher"));

    env->SetProtoMethod(t, "start", StatWatcher::Start);
    env->SetProtoMethod(t, "stop", StatWatcher::Stop);

    target->Set(FIXED_ONE_BYTE_STRING(env->isolate(), "StatWatcher"),
        t->GetFunction());
}

static void Delete(uv_handle_t* handle)
{
    delete reinterpret_cast<uv_fs_poll_t*>(handle);
}

StatWatcher::StatWatcher(Environment* env, Local<Object> wrap)
    : AsyncWrap(env, wrap, AsyncWrap::PROVIDER_STATWATCHER)
    , watcher_(new uv_fs_poll_t)
{
    MakeWeak<StatWatcher>(this);
    uv_fs_poll_init(env->event_loop(), watcher_);
    watcher_->data = static_cast<void*>(this);
}

StatWatcher::~StatWatcher()
{
    Stop();
    uv_close(reinterpret_cast<uv_handle_t*>(watcher_), Delete);
}

void StatWatcher::Callback(uv_fs_poll_t* handle,
    int status,
    const uv_stat_t* prev,
    const uv_stat_t* curr)
{
    StatWatcher* wrap = static_cast<StatWatcher*>(handle->data);
    NODE_CHECK_EQ(wrap->watcher_, handle);
    Environment* env = wrap->env();
    HandleScope handle_scope(env->isolate());
    Context::Scope context_scope(env->context());
    Local<Value> argv[] = {
        BuildStatsObject(env, curr),
        BuildStatsObject(env, prev),
        Integer::New(env->isolate(), status)
    };
    wrap->MakeCallback(env->onchange_string(), arraysize(argv), argv);
}

void StatWatcher::New(const FunctionCallbackInfo<Value>& args)
{
    NODE_CHECK(args.IsConstructCall());
    Environment* env = Environment::GetCurrent(args);
    new StatWatcher(env, args.This());
}

void StatWatcher::Start(const FunctionCallbackInfo<Value>& args)
{
    NODE_CHECK_EQ(args.Length(), 3);

    StatWatcher* wrap;
    ASSIGN_OR_RETURN_UNWRAP(&wrap, args.Holder());
    node::Utf8Value path(args.GetIsolate(), args[0]);
    const bool persistent = args[1]->BooleanValue();
    const uint32_t interval = args[2]->Uint32Value();

    if (!persistent)
        uv_unref(reinterpret_cast<uv_handle_t*>(wrap->watcher_));
    uv_fs_poll_start(wrap->watcher_, Callback, *path, interval);
    wrap->ClearWeak();
}

void StatWatcher::Stop(const FunctionCallbackInfo<Value>& args)
{
    StatWatcher* wrap;
    ASSIGN_OR_RETURN_UNWRAP(&wrap, args.Holder());
    Environment* env = wrap->env();
    Context::Scope context_scope(env->context());
    wrap->MakeCallback(env->onstop_string(), 0, nullptr);
    wrap->Stop();
}

void StatWatcher::Stop()
{
    if (!uv_is_active(reinterpret_cast<uv_handle_t*>(watcher_)))
        return;
    uv_fs_poll_stop(watcher_);
    MakeWeak<StatWatcher>(this);
}

} // namespace node
